Magnetic brake.



No. 642,274. Patented Ian. 30, I900. T. VUN ZWEIGBERGK.

MAGNETIC BRAKE.

(Application filed Apr. 279, 1899.)

(No Model.)

W ft aimm m z j 'y f Th. STATES PATENT OFFICE.

THORSTEN VON ZlVEIGBERGK, OF CLEVELAND, OHIO.

MAGNETIC BRAKE,

SPECIFICATION forming part of Letters Patent No. 642,274, dated January 30, 1900.

Application filed April 29, 1899. Serial No. 714,949. No model.)

To all whom it may concern:

Be it known that I, THORSTEN VON ZWEIG- BERGK, a subject of the King of Sweden and Norway, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Magnetic Brakes, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

My invention relates to brakes of that class which have shoes adapted to be thrown by an electric current into frictional engagement with an annular surface revolving on the axle or wheel it is desired to retard.

The object of the invention is to provide such a brake in a form which, while being very efficient in service, shall be very simple and cheap in construction, easily installed, and easily removed and repaired.

The invention consists of the means I employ for attaining this end, as hereinafter described, and definitely set out in the claims.

The drawingsclearly disclose my invention as applied to the axle of a railway-car in conjunction with the motor, whose frame is sleeved on that axle.

Figure 1 is a plan, partly sectional, of the brake-shoe and a portion of the motor-casing in place on the axle. Fig. 2 is an end view, partly sectional, of the motor-casing and its sleeve or bearing which takes around the axle. Fig. 3 is a face view of the brake-shoe complete, and Fig. 4 is a face view of the brakeshoe with the friction-plates and the movable end block removed. Fig. 5 is a face View of the annular friction member secured to the axle. Fig. 6 is a vertical edge view of the brake-shoe looking from the motor side of the axle. Fig. '7' is a fragmentary cross-section on the line '7 7 of Fig. Fig. 8 is a side elevation of the magnetic winding before it is put in place.

The same letters of reference designate the same parts in each figure.

Referring to the parts by letters, A represents the axle of the car, and B the wheel rigid with it.

O and 0 represent the upper and lower halves of the motor casing or frame. These halves are suitably secured together, and the frame is journaled on the axle by means of the wings, which extend from the two parts of the casing and are clamped together by the bolts 0 These wings have the faceplates 0 and c, as shown, and carry the brasseso. On each of the plates 0 and c, at the junction-line and at the front and rear edges, are formed angle or L shaped projections 0 and these projections abutting together make a T-shaped projection having a tongue and two wings, as shown in section lines in Fig. 2.

D represents the body of the brake-shoe, which carries the electric winding and friction-plates. This body is of the horseshoe shape shown and has on its face depressions and projections for receiving the winding. In use the body is closed at its open end or poles by the block E, which has tongues e taking into grooves in the faces of the opening which the block occupies. The block is thus slid into place and is held by the tongues and grooves against lateral displacement, and it is held against longitudinal movement by the bolt F, which passes through the projecting ends d of the member D and has on its end a nut f. The horseshoe and block are thus locked into one rigid annular member.

When the horseshoe and block E are bolted together, a substantially circular space is inolosed, which is modified at the block E and diametrically opposite in the body by suitable shoulders, preferably caused by rectangular notches e (1. These notches are of the proper size and position to engage with the shoulders caused by the tongues of the T- shaped projections formed of the lugs c c and be thereby rigidly and securely held against rotation.

As stated, the brake-body D has on its face depressions and projections for receiving the electric winding. The projections, which are integral with the body, are designated d They are of the elongated rounded-end shape shown. All around these projections and between the outer peripheral wall (1 and the inner peripheral wall (1 of the body is a connecting-recess, and between the consecutive projections (1 this recess is deepened by the diagonal depressions d.

The electric winding consists of a single wire 7L, coiled upon itself into a long linkshaped loop H, covered by an outside unit insulation. This loop is hooked around the first projection 61 and is then twisted upon itself one hundred and eighty degrees, the under loop lying in the first depression The sides of the loop thus cross each other and lie on opposite sides of the next projection d after which they are twisted one hundred and eighty degrees foreach projection encountered, the under loop in each case lying in the depression (i The loop II is thus brought into the position shown in Fig. 4, the wires passing out of the shoe through openings 01 at the ends of the recess therein. This makes an extremely cheap and simple winding, the current substantially encircles each projection (1 and the consecutive projections become magnet-cores of opposite polarity, thus making the braking-shoe in effect a system of horseshoe-magnets. The block E closes the magnetic circuit of the base D.

Friction rubbing-plates J (made preferably of cast-iron, having the inset cast-steel portionj) have on their inner faces bosses j, which are of the same shape as the projections d, and these bosses extend through similarlyshaped holes in the horseshoe-shaped coverplate I, of brass or other non-magnetic material, and are secured to the projections 61 by means of bolts K, passing through holes 01 near the ends of the projections (1 into the bosses. The friction-plates thus become the pole-pieces of the magnets, and the brass plate I, being of the channel shape shown, extends Within the peripheral walls 01 and d whereby the winding is entirely incased. Access to it may be easily had, however, and, moreover, the plates may be easily removed when worn out and replaced by new ones.

The cooperating braking surface with which the plates J are adapted to move into frictional engagement is rigid with the wheel and axle. It is designated L, and consists of an annular finished rubbing-surface Z, a central sleeve or hub Z, and a connecting-web Z This member is preferably cast in the circular form shown in Fig. 5, with elongated diametrically-opposed slots Z extending from near the central opening to near the periphery. After it has been bored for the axle and faced for the rubbing-surfa ce it is broken apart, and thus rough edges Z and Z are made at the ends of the slots Z which insure the two parts of the member coming into the same presentation when they are secured together around the axle.- The hub portion has grooves Z for receiving keys, preventing its turning, and it is clamped to the axle by bolts Z taking through flanges Z formed on said hub.

With the parts as shown as soon as an electric current flows over the coil H the body D becomes, as stated, a system of magnets and the pole-pieces J find their armatures in the disk L. The attraction thus engendered causes the member D to move toward the disk L, whereby the plates J come into friction with the annular surface}, the degree of which depends upon the amount of current flowing.

In order to prevent excessive movement of the member D should the member L become broken or to retain the member D in place if the member L is temporarily removed, I provide bolts G, which pass from the back side of the plates 0 o loosely through holes 0 therein and screw into the back side of the member D, and on these bolts are nuts g, which stand far enough from the back side of the plates 0 c to limit the movement of the mem ber D, but do not interfere with its operation.

Springs M, surrounding studs N, extending from the member D, hear at one end against the rear side of the plates 0 c and at the other against shoulders provided by the adjustable nuts P on the stud. Thus the member D is normally held out of engagement with the disk L, but is allowed to move into it with the proper braking force as soon as the current is applied. The studs N stand in the notches o in the plates 0 c, and thus do not interfere with the removal of the member D, which is accomplished by removing the bolts G and the bolt F and sliding the block E one way and the rest of the member the other way.

Having described my invention, I claim- 1. The combination of an annular braking member adapted to surround an axle and consisting of a horseshoe-shapedpiece carrying magnets, and a removable block fitting in between the poles of the horseshoe and closing the same, means for clamping said poles and block together, diametrically-opposed shoul ders on said block and horseshoe, and nonrotatable shoulders engaging with the shoulders first mentioned and holding the braking member against rotation, substantially as described.

2. The combination of a horseshoe-shaped member carrying magnets and adapted to extend around an axle, a block fittingin between the poles of the horseshoe, a bolt passing through said poles and block and clamping them together, diametrically-opposed shoulders on said block and member, and non-rotatable shoulders adapted to engage with the shoulders first mentioned and hold the member against rotation, substantially as described.

3. The combination,with an axle,of a horseshoe-shaped member D around the axle, a block E, tongues and grooves between said block and member whereby the block may slide into place to close the ends thereof, a bolt adapted to clamp said parts together, non-rotatable shoulders adapted to engage with shoulders on said block and member whereby the member is prevented from rotating, said member carrying magnet-cores and a magnet-winding, and a cooperating member revolving with the axle and serving as an armature for said magnets, substantially as described.

4:. The combination, with an axle, of a motor-frame sleeved thereon, said sleeve includ= ing two plates cc, said plates having at their junction-line abutting projections 0 and an annularbrakingmember consisting ofahorseshoe-shaped piece and aremovable block connecting the poles of the horseshoe, said member surrounding said projections and having notches into which the projections may take, one of said notches being in the removable block, whereby, when the block is removed, the rest of the member maybe removed, substantially as described.

5. The combination, with an axle, of a motor-frame sleeved thereon, said sleeve including two plates 0 c, said plates having at their junction -line the l..-shaped projections 0 which projections when placed together become T-shaped, an annular braking member surrounding said projections and having notches into which the body of the T-shaped projections take, the heads of the T-shaped projections lying against the member on each side of the notches, substantially as described.

6. A magnetic brake-shoe consisting of a member D, a plurality of annularly-placed elongated projections d on one face thereof, an electric coil H formed in a continuous loop and passing on both sides of each projection, the coil crossing itself between the projec tions, substantially as described.

7. A brake member having a series of elongated projections (Z on one face, depressions d between these projections, and an electric coil formed in one continuous loop and lying on opposite sides of each projection and crossing itself between them, the under branch lying in the depression (1 at said crossing and the coil looping around the end projections (1 substantially as described.

8. A m ultipolar magnet consisting of abody with a series of projections and a loop of coiled conducting material terminating with leading-in wires, said loop being drawn around one projection, then twisted on itself, then around the next, then twisted on itself, then around the next projection,and so on ,Whereby said projections become magnetic cores of opposite polarity, substantially as described.

9. A magnetic brake-shoe consisting of a member D having a series of projections d on one face thereof, an electric coil H formed in one continuous loop and lying on opposite sides of each projection and crossing itself between the projections whereby the consecutive projections become cores of opposite polarity, a non-magnetic cover-plate for inclosing the coil and separated rubbing-plates secured to the projections, substantially as described.

10. The combination with an axle, a motorframe sleeved thereto, said sleeve carrying the plates 0 c, said plates having the projections 0 and the notches a a braking member D having shoulders adapted to engage with the projections 0 a pair of studs N eX- tending from said member D and lying in the notches c and springs M surrounding said studs and held between shoulders thereon at the rear side of the plates 0 c, substantially as described.

11. An insulated conductor h coiled into a loop H, the conductors constituting the loop being collectively surrounded by an insulating-covering, combined with a brake-shoe having a series of projections around which said loop takes, said loop crossing itself between the projections and thus lying on opposite sides of consecutive projections, substantially as described.

' In testimony whereof I hereunto aflix my signature in the presence of two witnesses. THORSTEN VON ZWEIGBERGK. \Vitnesses:

ALBERT l-I. BATES, PHILIP E. KNOWLTON. 

